It is well-known to use fenders which are elastomeric bodies hanging from ropes along the hull of a boat and which are inserted between the boat and the quayside when the boat comes alongside, thus protecting the hull against shock and wear. Unfortunately, as the fenders are hung vertically, there is very little protection against roll, which causes the boat to move along the vertical axis. In addition, when the boat comes alongside an articulated pontoon, fenders have the unfortunate disadvantage of bouncing off the pontoon when a person jumps onto the latter.
Fenders also exist, which are attached to pontoons or to quays. But because the latter are fixed, they do not protect the hull against wear when the boat is subjected to rolling.
The best system consists therefore of installing moving rollers around a fixed axis, either on the boat, or to the pontoon. A device of this kind is described in U.S. Pat. No. 3,145,685. It includes an axis on which a plurality of rubber rollers are mounted for absorbing the energy of shocks when the boat is subjected to vertical movements. Unfortunately, boat movements produced by turbulence in the water are not only vertical, and a boat is almost always subjected to horizontal movements which result in the boat rotating in one direction or another. In this case, unless rollers are fitted all along the boat or all along the pontoon, which would be exorbitant in cost terms, the boat is no longer protected by a roller at either end and its hull then strikes along the protruding axis, typically made of metal, at either end of the rollers, as in the patent referred to above.